|Publication number||US4751528 A|
|Application number||US 07/094,664|
|Publication date||Jun 14, 1988|
|Filing date||Sep 9, 1987|
|Priority date||Sep 9, 1987|
|Also published as||CA1318547C, DE3883371T2, EP0333819A1, EP0333819A4, EP0333819B1, US4951067, WO1989002576A1|
|Publication number||07094664, 094664, US 4751528 A, US 4751528A, US-A-4751528, US4751528 A, US4751528A|
|Inventors||Charles W. Spehrley, Jr., Linda T. Creagh, Robert R. Schaffer|
|Original Assignee||Spectra, Inc.|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (2), Referenced by (147), Classifications (19), Legal Events (7)|
|External Links: USPTO, USPTO Assignment, Espacenet|
This invention relates to ink jet systems and, more particularly, to a new and improved ink jet apparatus for use with hot melt inks providing controlled solidification of such inks.
Ink jet systems using inks prepared with water or other vaporizable solvents require drying of the ink (i.e., vaporization of the solvent) after it has been applied to a substrate, such as paper, which is supported by a platen. To facilitate drying of solvent-based inks, heated platens have previously been provided in ink jet apparatus.
Certain types of ink jet apparatus use inks, called "hot melt" inks, which contain no solvent and are solid at room temperature, are liquefied by heating for jet application to the substrate, and are resolidified by freezing on the substrate after application. In addition, the application of hot melt ink to a substrate by an ink jet apparatus transfers heat to the substrate. Moreover, the solidification of hot melt ink releases further thermal energy which is transferred to the substrate and supporting platen, which does not occur with the application of solvent-based inks. With high-density coverage this can raise the temperature of the paper and the platen above limits for acceptable ink penetration.
In order to control the penetration of hot melt inks into a permeable substrate such as paper to the desired extent, it is advantageous to preheat the substrate to a temperature close to but below the melting point of the hot melt ink. If the substrate temperature is too cold, the ink freezes after a short distance of penetration. This results in raised droplets and images with an embossed characteristic. Additionally, such ink droplets or images may have poor adhesion or may easily be scraped off or flake off by action of folding or creasing or may be subject to smearing or offsetting to other sheets. If the paper temperature is too high, for example, higher than the melting point of the ink, the ink does not solidify before it has penetrated completely through the paper, resulting in a defective condition called "print-through". In addition, an image printed on a substrate which is at a temperature in the vicinity of the melting point of the hot melt ink will appear noticeably different than an image printed at a lower substrate temperature. Such images exhibit characteristics of larger-than-normal spot size, fuzzy edges, blooming of fine lines and the like. Furthermore, contrary to the conditions required for the use of solvent-based inks in an ink jet apparatus, heating of the substrate after the ink has been deposited is ineffective to control the spread of the drops and to prevent the above-mentioned difficulties which may occur when using hot melt inks. Consequently, presently known ink jet apparatus using unheated or even heated-only platens are incapable of maintaining the conditions required for effective application of hot melt ink to a substrate to produce constant high-quality images.
Accordingly, it is an object of the present invention to provide a new and improved ink jet apparatus which is effective to overcome the above-mentioned disadvantages of the prior art.
Another object of the present invention is to provide an ink jet apparatus which is especially adapted for use with hot melt inks.
These and other objects and advantages of the invention are attained by providing an ink jet apparatus having a substrate-supporting, thermally conductive platen and a heater and a thermoelectric cooling arrangement both disposed in heat communication with the platen and including a heat pump for extracting heat from the platen in a controlled manner. Preferably, the apparatus also includes a temperature control system for controlling the heat pump and a thermoelectric heater responsive to the temperature control system for supplying heat to the platen when required to maintain a desired temperature. In addition, the platen preferably includes a vacuum system to retain the substrate in heat transfer relation to the platen during operation.
Further objects and advantages of the invention will be apparent from a reading of the following description in conjunction with the accompanying drawings in which:
FIG. 1 is a graphical representation showing the heat input to a platen supporting a sheet substrate being printed with an ink jet for various sheet printing times and print coverage values;
FIG. 2 is a schematic sectional view illustrating a representative temperature-controlled platen arrangement in accordance with the present invention;
FIG. 3 is a schematic sectional view taken along the lines III--III of FIG. 2 and looking in the direction of the arrows; and
FIG. 4 is a schematic sectional view illustrating another embodiment of the invention and showing the energy flux into and out of the paper and platen system.
In ink jet printing, the spot size on the paper depends on the initial drop volume and the degree to which this drop interacts with the substrate, said interaction affecting the degree of spread. In water-based ink jet systems, the ink wets the fibers and the drop tends to spread until fully absorbed by the fibers. This is generally considered a deficiency, since the absorbing characteristics of a range of plain papers is so great as to produce widely different print characteristics on different papers. In hot melt ink printing systems, the ink also wets the paper fibers, but the drop spread is limited by the cooling of the ink, which shares its thermal energy with the paper fibers until it freezes or until its viscosity becomes so high as to limit spreading motion. Fortunately, most papers have reasonably similar specific heats so that the drop spread is determined largely by the initial temperature of the ink drop and paper substrate in relation to the solidification temperature of the ink. As a consequence of the similarity of thermal characteristics of papers, similar images may be obtained on different papers if the substrate temperature is properly controlled.
In hot melt ink jet printers, the thermal energy applied to a unit area of a substrate such as paper depends upon the temperature of the hot melt ink when it reaches the substrate, the energy of solidification of the hot melt ink and the coverage of the substrate with ink during the printing. The temperature of the substrate immediately after printing depends upon the thermal energy applied during printing, the initial temperature of the substrate, and the temperature of a heat-conductive element such as a platen with which the substrate is in heat transfer relation.
Thus, a hot melt ink which solidifies at a selected temperature below the temperature at which it is applied to the substrate may solidify almost immediately if the substrate and its supporting platen are at a low temperature, substantially below the selected temperature, which may occur during start-up of the system. Such immediate solidification prevents sufficient penetration of the hot melt ink into the substrate before it solidifies. On the other hand, if the substrate and its supporting platen are at a temperature close to or above the solidification temperature of the hot melt ink, a relatively long time, such as several seconds, may be required for solidification, thereby permitting uncontrolled drop spread or print-through of the printed image. For example, a modern high-speed hot melt printer with a 96-jet head applying two layers of ink drops of different colors at a temperature of 130° C. to a substrate at a rate of 12,000 drops per second per jet with a linear density of 300 dots per inch, providing a total ink thickness of 0.9 mil, raises the bulk temperature of a 4-mil paper substrate by about 21° C. during the printing operation. With continued printing of a substrate which moves over a fixed platen in that manner, the platen temperature soon reaches a level approaching or above the solidification point of the hot melt ink.
FIG. 1 of the accompanying drawings illustrates schematically in graphical form the heat energy applied to a supporting platen when an 8.5"×11" paper sheet moving across the platen is being printed with hot melt ink.
As described hereinafter with reference to FIG. 4, there are a plurality of energy fluxes which determine whether there is a net heat input to the paper/platen system, in which case the temperature will tend to rise, or whether there is a net heat outflow from the paper/platen system, in which case the temperature in the printing zone will decrease. Heat energy is inputted to the system by heat transfer from the heated printhead across the airgap via conduction, convection and radiation, by the enthalpy in the ink drops, by the optional electrical power provided selectively by the heater controller, and by the heat content of the paper which enters the system. Energy outflow from the system includes heat energy in the paper and ink (which exits at a temperature higher than the paper's input temperature), heat transfer from the platen and from the paper which is not covered by the printhead to the surrounding air via convection, heat transferred from the platen to the surrounding structure via conduction through mounts and/or selectively via heat pump action of thermoelectric coolers.
As shown in FIG. 1, the heat input, represented by the ordinate in the graph, increases with increasing sheet printing time and with increasing percent coverage of the substrate. In this illustration, typical sheet printing times from about 10 seconds minimum to about 33 seconds maximum are shown and, as shown in the graph, the highest net heat input occurs at the slowest sheet printing time because the slowly moving sheet removes less thermal energy from the paper/platen system than is delivered by the enthalpy in the hot ink drops and by thermal transfer from the printhead to the paper/platen system.
Similarly, at any given sheet printing time, the heat input to the platen increases with increasing printing coverage, which is the percentage of sheet area covered by ink. Where two or more different colored inks are applied, the colored inks usually overlie each other at least to some extent. Consequently, the graphical illustration in FIG. 1 illustrates the heat input to the platen not only for 50% and 100% sheet coverage, but also for sheet coverage in excess of 100%, such as 150% and 200%, which corresponds to coverage of the entire sheet by two layers of ink. In general, sheets with lower coverage require less printing time.
FIG. 1 illustrates heat input to the platen under various printing conditions in four sections labelled I, II, III and IV. Section I shows the heat input to the platen when printing the 7"×9" normal full text area of an 8.5"×11" sheet with up to full density with a single layer of hot melt ink. When up to two full layers of hot melt ink are applied in overlying relation to the sheet during color printing, the heat energy transferred to the platen is illustrated in the section designated II. In that case, as shown in FIG. 1, up to twice the heat energy is transferred to the platen.
The section designated III in FIG. 1 illustrates the heat input to the platen when printing a single layer of ink at up to full density on a "full page" area of an 8.5"×11" sheet, i.e., to within 0.38" of the top left and bottom edges and within 0.10" of the right edge of the sheet, and the section designated IV illustrates the heat input for full-page area printing with up to a double layer of hot melt ink. With color printing of solid area patterns, such as pie charts or the like, operation is frequently in the region designated III and IV, providing very high thermal energy input to the platen.
The platen temperature depends not only on the rate of heat input, but also on the rate of removal of heat energy from the platen. To maintain a selected platen temperature assuring proper operation of a hot melt ink jet apparatus, especially under conditions such as are shown in sections III and IV, therefore, heat energy must be removed rapidly and efficiently from the platen. It has been found that removal of the heat energy from a platen by conduction or convection to a moving air stream may be inadequate, especially when the local ambient air temperature rises to within 5° or 10° C. of the operating set point. At these and other times, the system is incapable of sufficiently precise control to maintain the platen temperature within desired limits for optimum operation.
For example, on initial start-up, a conductively or convectively cooled platen will be at room temperature (i.e., 21° C.) whereas, in order to allow sufficient penetration of a hot melt ink into a fibrous substrate such as paper prior to solidification, it is desirable to maintain the substrate at about 40° C. On start-up, therefore, the addition of heat to the platen is necessary. On the other hand, when continuous printing of the type described above occurs using hot melt ink at 130° C., for example, the platen temperature quickly reaches and exceeds 40° C. and approaches the solidification temperature of the hot melt ink, thereby requiring removal of heat from the platen. Furthermore, frequent and extreme changes in the printing rate such as occur in the reproduction of solid-colored illustrations such as pie charts intermittently with single-color text will cause corresponding extreme fluctuations in the temperature of the platen and the substrate being printed, resulting in alternating conditions of print-through and insufficient ink penetration into the substrate.
In the representative embodiment of the invention illustrated in FIGS. 2 and 3, the platen temperature of a hot melt ink jet apparatus is maintained at a desired level to provide continuous optimum printing conditions. As shown in FIG. 2, a sheet or web 10 of a substrate material such as paper is driven by a drive system including a set of drive rolls 11 and 12 which rotate in the direction indicated by the arrows to move the substrate material through the gap between an ink jet head 13 and a platen assembly 14. The ink jet head is reciprocated perpendicularly to the plane of FIG. 2 so as to project an array of ink jet drops 15 onto the surface of the substrate in successive paths extending transversely to the direction of motion of the web 10 in a conventional manner. The platen assembly 14 includes a platen 16 mounted in a housing 17 having slit openings 18 and 19 at the upper and lower edges of the platen 16 and an exhaust outlet 20 at the rear of the housing leading to a vacuum pump 21 or blower. The housing 17 may be substantially airtight, or for purposes of substantially continuous heat removal to the air, even when paper covers the face openings, additional air ports may be provided. As best seen in FIG. 3, the platen 16 and the adjacent vacuum slits 18 and 19 extend substantially across the width of the web 10 of substrate material and the web is driven by three drive rolls 11 which form corresponding nips with adjacent pinch rolls 12, one of which is shown in FIG. 2.
To assure that the temperature of the substrate 10 is maintained at the desired level to permit sufficient penetration of the hot melt ink drops 15 without permitting print-through, a temperature control unit 22 detects the temperature of the platen 16 through a line 23. If it is necessary to heat the platen to maintain the desired platen temperature, for example, on start-up of the apparatus or when printing at low coverage or with low sheet printing times, the control unit 22 supplies power through a line 24 to a conventional resistance-type heater or thermistor 25 to heat the platen until it reaches the desired temperature of operation.
In addition, an electrical heat pump 26 is connected by a line 27 to a thermoelectric cooler 28, for example, of the type designated CP 1.0-63-06L, available from Melcor, which is in thermal contact with the platen 16. When the temperature control unit 22 detects a platen temperature above the desired level resulting, for example, from printing at high coverage or with high sheet printing times, it activates the heat pump through a line 29 to transfer thermal energy from the thermoelectric cooler 28 through the line 27 to the pump which in turn transfers thermal energy to a heat sink 30. The heat sink 30, which may, for example, be a structural support member for the entire platen assembly, has fins 31 for radiative and convective heat dissipation and is provided with a forced air cooling arrangement 32 to assure a high enough rate of heat removal to permit the heat pump 26 to maintain the desired platen temperature. If extreme conditions are encountered in which the heat energy is supplied to the web 10 and the platen 16 by the ink jet head 13 at a rate which exceeds the capacity of the thermoelectric cooler 28 and the heat pump 26 to maintain the desired temperature, the control unit 22 may send a command signal through a line 33 to an ink jet system control device 34 which will reduce the rate at which ink drops are applied by the ink jet head 13 to the web 10 until the heat pump 26 is again able to maintain a constant platen temperature.
Although the platen temperature is thus controlled to assure prompt solidification of the ink drops in the array 15 after sufficient penetration into the substrate 10, the temperature of the solidified ink drops may not be low enough when the substrate reaches the nip between the drive rolls 11 and the pinch rolls 12 to prevent offsetting of ink onto the pinch roll 12 opposite the center drive roll 11 shown in FIG. 3. To avoid that possiblity, a small quench zone is provided by another thermoelectric cooler 35 connected by a line 36 to the heat pump 26 which is arranged to maintain a temperature in that zone at least 10° C. lower than the temperature of the platen 16 in order to assure complete solidification of the ink in that zone.
As shown in FIG. 3, the thermoelectric cooler 35 is aligned with the drive roll 11 and its associated pinch roll so that the strip of the web 10 which passes between those rolls is cooled by the element 35. At the edges of the web 10, on the other hand, the other drive rolls 11 and their associated pinch rolls are positioned in a narrow margin in which no printing occurs. Consequently, quenching is unnecessary in those regions.
In another platen embodiment, the quench zone downstream of the temperature-controlled platen may be provided completely across the width of the paper. Said quench zone may be, for example, a portion of the platen support member which has adequate heat sink capability.
In operation, the platen 16 is heated if necessary by the heater 25 to raise it to the desired temperature, such as 40° C. The vacuum pump 21 exhausts air from the housing 17 and draws air through the apertures 18 and 19, as indicated by the arrows in FIG. 2, to hold the web 10 in thermal contact with the platen 16 as it is advanced by the drive rolls 11 and associated pinch rolls 12. The ink jet head 13 sprays hot melt ink 15 onto the web 10 and the resulting increase in platen temperature is detected by the control unit 22, causing the heat pump 20 to transfer thermal energy from the thermoelectric cooler 28 to the heat sink 30 and the fins 31 from which it is removed by the forced-air cooling system 32.
For conventional hot melt inks, the ink jet head 13 maintains the ink at a jetting temperature of, for example, 130° C., but the ink solidifies at, for example, 60° C. and, to assure solidification after the desired degree of penetration but before print-through occurs, the platen 16 should be maintained within about 3°-5° C. of a selected lower temperature, for example, 40° C. During normal operation of the ink jet apparatus, however, the ambient temperature of the platen assembly 14 and its surrounding components may be at or above 40° C. Accordingly, the heat pump 26 may be arranged to transfer heat continuously from the thermoelectric coolers 28 and 32 to the heat sink 30 even during quiescent periods in the operation of the system. During ink jet operation, moreover, especially operation in regions II and IV in FIG. 1, substantially more heat is extracted from the platen and transferred to the heat sink 30, which may thus be heated to a relatively high temperature of, for example, 60°-65° C., and the heat energy is removed from the heat sink 30 and the fins 31 by the forced-air system 32. At the same time, the thermoelectric cooler 32 in the quench zone is maintained about 10° C. cooler than the rest of the platen, for example, at 30° C., assuring complete solidification of ink before engagement by a pinch roll.
Because the size and nature of the printed image may vary widely, it is necessary to use a temperature-controlled platen with high lateral thermal conductivity in order to minimize temperature gradients from one side to the other. Aluminum and copper are suitable platen materials, but the cross-sectional area of the platen must be significant, on the order of 0.5 square inch or larger in the case of aluminum. Such platens are massive and may take much space and require high power or long times to heat up to operating temperature. For these reasons, a structure embodying the characteristics of a heat pipe with evaporation and condensation of liquid to transfer energy may be employed.
Other problems may occur in the control of the web as it moves across the platen in the print zone. One such problem relates to differential thermal expansion of film media (e.g., Mylar) and another relates to differential shrinkage of paper as it is heated and dried by the platen. In these cases, the web may buckle or cockle and move off the platen surface by 0.005 or more inches, which degrades the thermal connection between paper and platen and which also degrades dot placement accuracy by changing the point of impact of the jets, especially in the case of bidirectional printing.
To avoid these problems, the platen configuration shown in FIG. 4 may be used. In this arrangement, an ink jet head 41 projects ink drops 42 toward a web of paper 43 supported by a curved platen 44 which causes the paper 43 to be held in curved configuration and thereby stiffened against buckling and cockling. A suitable curved platen 44 has a radius of curvature of about 5 to 10 inches has a temperature-controlled portion 45 of the type described with reference to FIG. 2 in the printing zone and a curved inlet portion 46 and a curved outlet portion 47. The inlet and outlet portions 46 and 47 extend at least 10° ahead of and 10° after the temperature-controlled portion 45. Thus, the temperature-controlled portion need not extend for the entire length of the curved paper path, but may occupy only about one-half inch of paper length, the inlet portion 46 and outlet portion 47 of the curved paper path being at temperatures which are more suitable for paper handling or quenching prior to passing into paper feed rolls of the type shown in FIG. 2. A housing 48 encloses the temperature-control zone for the platen 45 and a temperature-control component 49 which may include a thermoelectric cooler of the type described with reference to FIG. 2 are mounted in contact with the platen 45 in the temperature-control zone. A power line 50 energizes the heater in the portion 45 when it is necessary to add heat to the platen.
In the arrangement shown in FIG. 4, the energy flux into and out of the paper/platen system is represented as follows:
Energy Flux Into Paper/Platen System
ql =radiant heat transfer from ink jet head 41.
q2 =conduction through the air.
q3 =convection from ink jet head 41 to platen.
E=enthalpy in the ink drops.
q4 =heat energy in entering paper at temperature Tin.
p=heat transferred by heater into platen.
Enerqy Flux Out of Paper/Platen System
q5 =heat energy exiting with the paper and ink at temperature Tout.
q6 =heat energy removed from platen by convective heat transfer to the air.
q7 =heat removed from platen by conduction through mounts and/or by heat pump action.
Although the invention has been described herein with reference to a specific embodiment, many modifications and variations therein will readily occur to those skilled in the art. Accordingly, all such variations and modifications are included within the intended scope of the invention as defined by the following claims.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US4140907 *||Jul 20, 1977||Feb 20, 1979||Nippon Telegraph And Telephone Public Corporation||Thermal-plain paper recording system|
|US4593292 *||Oct 15, 1984||Jun 3, 1986||Exxon Research And Engineering Co.||Ink jet apparatus and method of operating ink jet apparatus employing phase change ink melted as needed|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US4889761 *||Aug 25, 1988||Dec 26, 1989||Tektronix, Inc.||Substrates having a light-transmissive phase change ink printed thereon and methods for producing same|
|US4951067 *||Jun 3, 1988||Aug 21, 1990||Spectra, Inc.||Controlled ink drop spreading in hot melt ink jet printing|
|US4971408 *||Nov 15, 1988||Nov 20, 1990||Spectra, Inc.||Remelting of printed hot melt ink images|
|US5023111 *||Oct 2, 1989||Jun 11, 1991||Spectra, Inc.||Treatment of hot melt ink images|
|US5043741 *||Jun 12, 1990||Aug 27, 1991||Spectra, Inc.||Controlled ink drop spreading in hot melt ink jet printing|
|US5099256 *||Nov 23, 1990||Mar 24, 1992||Xerox Corporation||Ink jet printer with intermediate drum|
|US5105204 *||Jul 27, 1990||Apr 14, 1992||Spectra, Inc.||Subtractive color hot melt ink reflection images on opaque substrates|
|US5114747 *||Feb 6, 1991||May 19, 1992||Spectra, Inc.||Treatment of hot melt ink images|
|US5151120 *||Apr 12, 1991||Sep 29, 1992||Hewlett-Packard Company||Solid ink compositions for thermal ink-jet printing having improved printing characteristics|
|US5196241 *||Apr 8, 1991||Mar 23, 1993||Tektronix, Inc.||Method for processing substrates printed with phase-change inks|
|US5281442 *||Jan 22, 1992||Jan 25, 1994||Spectra, Inc.||Treatment of hot melt ink images|
|US5287123 *||May 1, 1992||Feb 15, 1994||Hewlett-Packard Company||Preheat roller for thermal ink-jet printer|
|US5296873 *||May 1, 1992||Mar 22, 1994||Hewlett-Packard Company||Airflow system for thermal ink-jet printer|
|US5323176 *||Sep 9, 1992||Jun 21, 1994||Brother Kogyo Kabushiki Kaisha||Printer with a selectively operable heating processor|
|US5329295 *||May 1, 1992||Jul 12, 1994||Hewlett-Packard Company||Print zone heater screen for thermal ink-jet printer|
|US5392065 *||Sep 15, 1992||Feb 21, 1995||Brother Kogyo Kabushiki Kaisha||Ink jet printer using hot melt ink|
|US5399039 *||Apr 30, 1993||Mar 21, 1995||Hewlett-Packard Company||Ink-jet printer with precise print zone media control|
|US5406316 *||Apr 30, 1993||Apr 11, 1995||Hewlett-Packard Company||Airflow system for ink-jet printer|
|US5406321 *||Apr 30, 1993||Apr 11, 1995||Hewlett-Packard Company||Paper preconditioning heater for ink-jet printer|
|US5411825 *||Oct 16, 1990||May 2, 1995||Xerox Corporation||Heat development process of migration imaging members|
|US5428384 *||Feb 18, 1994||Jun 27, 1995||Hewlett-Packard Company||Heater blower system in a color ink-jet printer|
|US5446487 *||Dec 20, 1993||Aug 29, 1995||Hewlett-Packard Company||Air evacuation system for ink-jet printer|
|US5456543 *||May 2, 1994||Oct 10, 1995||Hewlett-Packard Company||Printer motor drive with backlash control system|
|US5461408 *||Apr 30, 1993||Oct 24, 1995||Hewlett-Packard Company||Dual feed paper path for ink-jet printer|
|US5467119 *||Oct 14, 1993||Nov 14, 1995||Hewlett-Packard Company||Ink-jet printer with print heater having variable heat energy for different media|
|US5479199 *||Apr 30, 1993||Dec 26, 1995||Hewlett-Packard Company||Print area radiant heater for ink-jet printer|
|US5500658 *||Jul 20, 1994||Mar 19, 1996||Canon Kabushiki Kaisha||Ink jet recording apparatus having a heating member and means for reducing moisture near an ink discharge port of a recording head|
|US5506609 *||Jun 30, 1993||Apr 9, 1996||Apple Computer, Inc.||Minimizing color bleed while maximizing throughput for color printing|
|US5510822 *||Aug 24, 1993||Apr 23, 1996||Hewlett-Packard Company||Ink-jet printer with heated print zone|
|US5521622 *||Oct 7, 1994||May 28, 1996||Hewlett-Packard Company||Print quality optimization for a color ink-jet printer by using a larger nozzle for the black ink only|
|US5532720 *||Sep 15, 1993||Jul 2, 1996||Quad/Tech, Inc.||Solvent recovery system for ink jet printer|
|US5539437 *||Jan 10, 1994||Jul 23, 1996||Xerox Corporation||Hybrid thermal/hot melt ink jet print head|
|US5581289 *||Apr 30, 1993||Dec 3, 1996||Hewlett-Packard Company||Multi-purpose paper path component for ink-jet printer|
|US5589866 *||Jan 13, 1995||Dec 31, 1996||Hewlett-Packard Company||Air evacuation system for ink-jet printer|
|US5593486 *||Dec 5, 1995||Jan 14, 1997||Xerox Corporation||Photochromic hot melt ink compositions|
|US5622897 *||Jul 8, 1994||Apr 22, 1997||Compaq Computer Corporation||Process of manufacturing a drop-on-demand ink jet printhead having thermoelectric temperature control means|
|US5655201 *||Dec 21, 1995||Aug 5, 1997||Xerox Corporation||Tapered rollers for migration imaging system|
|US5667568 *||Mar 29, 1996||Sep 16, 1997||Xerox Corporation||Hot melt ink compositions|
|US5688312 *||Mar 29, 1996||Nov 18, 1997||Xerox Corporation||Ink compositions|
|US5693128 *||Jan 21, 1997||Dec 2, 1997||Xerox Corporation||Phase change hot melt ink compositions|
|US5698017 *||Sep 27, 1996||Dec 16, 1997||Xerox Corporation||Oxazoline hot melt ink compositions|
|US5700316 *||Mar 29, 1996||Dec 23, 1997||Xerox Corporation||Acoustic ink compositions|
|US5723202 *||Apr 29, 1994||Mar 3, 1998||Hewlett-Packard Co.||Transparent printer media with reflective strips for media sensing|
|US5747554 *||Mar 29, 1996||May 5, 1998||Xerox Corporation||Ink compositions|
|US5751303 *||Nov 10, 1994||May 12, 1998||Lasermaster Corporation||Printing medium management apparatus|
|US5774141 *||Oct 26, 1995||Jun 30, 1998||Hewlett-Packard Company||Carriage-mounted inkjet aerosol reduction system|
|US5774155 *||Oct 25, 1996||Jun 30, 1998||Hewlett-Packard Company||Ink-jet printer having dual drying system|
|US5793398 *||Nov 29, 1995||Aug 11, 1998||Levi Strauss & Co.||Hot melt ink jet shademarking system for use with automatic fabric spreading apparatus|
|US5844020 *||Mar 31, 1997||Dec 1, 1998||Xerox Corporation||Phase change ink compositions|
|US5855836 *||Jun 12, 1997||Jan 5, 1999||3D Systems, Inc.||Method for selective deposition modeling|
|US5876492 *||Sep 23, 1997||Mar 2, 1999||Xerox Corporation||Ink compositions containing esters|
|US5902390 *||Sep 23, 1997||May 11, 1999||Xerox Corporation||Ink compositions containing ketones|
|US5922117 *||Sep 23, 1997||Jul 13, 1999||Xerox Corporation||Ink compositions containing alcohols|
|US5931995 *||Sep 23, 1997||Aug 3, 1999||Xerox Corporation||Ink compositions|
|US5958119 *||Sep 23, 1997||Sep 28, 1999||Xerox Corporation||Hot melt ink compositions|
|US5980981 *||Feb 6, 1991||Nov 9, 1999||Fulton; Steven J.||Method of preparing a transparency having a hot melt ink pattern|
|US5989325 *||Mar 5, 1998||Nov 23, 1999||Xerox Corporation||Ink compositions|
|US6045607 *||Mar 30, 1999||Apr 4, 2000||Xerox Corporation||Ink compositions|
|US6059406 *||Jun 3, 1997||May 9, 2000||Hewlett-Packard Company||Heater blower system in a color ink-jet printer|
|US6059871 *||Nov 30, 1998||May 9, 2000||Xerox Corporation||Ink compositions|
|US6066200 *||Apr 27, 1999||May 23, 2000||Xerox Corporation||Ink compositions|
|US6071333 *||Apr 27, 1999||Jun 6, 2000||Xerox Corporation||Ink compositions|
|US6086661 *||Apr 27, 1999||Jul 11, 2000||Xerox Corporation||Ink compositions|
|US6096124 *||Apr 27, 1999||Aug 1, 2000||Xerox Corporation||Ink compositions|
|US6096125 *||Apr 27, 1999||Aug 1, 2000||Xerox Corporation||Ink compositions|
|US6106115 *||Sep 18, 1997||Aug 22, 2000||Hewlett-Packard Company||Image forming method using transparent printer media with reflective strips for media sensing|
|US6106599 *||Jun 29, 1999||Aug 22, 2000||Xerox Corporation||Inks|
|US6106601 *||Apr 27, 1999||Aug 22, 2000||Xerox Corporation||Ink compositions|
|US6110265 *||Apr 27, 1999||Aug 29, 2000||Xerox Corporation||Ink compositions|
|US6132499 *||Jul 29, 1999||Oct 17, 2000||Xerox Corporation||Inks|
|US6133355 *||Jun 12, 1997||Oct 17, 2000||3D Systems, Inc.||Selective deposition modeling materials and method|
|US6187082||Mar 30, 1999||Feb 13, 2001||Xerox Corporation||Ink compositions|
|US6188051||Jun 1, 1999||Feb 13, 2001||Watlow Polymer Technologies||Method of manufacturing a sheathed electrical heater assembly|
|US6193349||Jun 18, 1997||Feb 27, 2001||Lexmark International, Inc.||Ink jet print cartridge having active cooling cell|
|US6233398||Mar 24, 1999||May 15, 2001||Watlow Polymer Technologies||Heating element suitable for preconditioning print media|
|US6263158||May 11, 1999||Jul 17, 2001||Watlow Polymer Technologies||Fibrous supported polymer encapsulated electrical component|
|US6287373||Jun 22, 2000||Sep 11, 2001||Xerox Corporation||Ink compositions|
|US6305769||Jun 13, 1997||Oct 23, 2001||3D Systems, Inc.||Selective deposition modeling system and method|
|US6306203||Aug 28, 2000||Oct 23, 2001||Xerox Corporation||Phase change inks|
|US6319310||May 22, 2000||Nov 20, 2001||Xerox Corporation||Phase change ink compositions|
|US6322619||Feb 22, 2000||Nov 27, 2001||Xerox Corporation||Ink compositions|
|US6328440 *||Jan 7, 2000||Dec 11, 2001||Hewlett-Packard Company||Buckling control for a heated belt-type media support of a printer|
|US6328793||Aug 3, 2000||Dec 11, 2001||Xerox Corporation||Phase change inks|
|US6334890||Jun 22, 2000||Jan 1, 2002||Xerox Corporation||Ink compositions|
|US6336722||Oct 5, 1999||Jan 8, 2002||Hewlett-Packard Company||Conductive heating of print media|
|US6336963||Aug 3, 2000||Jan 8, 2002||Xerox Corporation||Phase change inks|
|US6350795||Jun 7, 2000||Feb 26, 2002||Xerox Corporation||Ink compositions|
|US6372030||Aug 3, 2000||Apr 16, 2002||Xerox Corporation||Phase change inks|
|US6392206||Aug 4, 2000||May 21, 2002||Waltow Polymer Technologies||Modular heat exchanger|
|US6392208||Aug 6, 1999||May 21, 2002||Watlow Polymer Technologies||Electrofusing of thermoplastic heating elements and elements made thereby|
|US6395077||Aug 3, 2000||May 28, 2002||Xerox Corporation||Phase change inks|
|US6398857||Aug 3, 2000||Jun 4, 2002||Xerox Corporation||Phase change inks|
|US6406140||Dec 8, 2000||Jun 18, 2002||Hewlett-Packard Company||Anisotropic thermal conductivity on a heated platen|
|US6432184||Aug 24, 2000||Aug 13, 2002||Xerox Corporation||Ink compositions|
|US6432344||Nov 4, 1998||Aug 13, 2002||Watlow Polymer Technology||Method of making an improved polymeric immersion heating element with skeletal support and optional heat transfer fins|
|US6433317||Apr 7, 2000||Aug 13, 2002||Watlow Polymer Technologies||Molded assembly with heating element captured therein|
|US6434328||Apr 23, 2001||Aug 13, 2002||Watlow Polymer Technology||Fibrous supported polymer encapsulated electrical component|
|US6460990 *||Dec 1, 2000||Oct 8, 2002||Hewlett-Packard Co.||Non-warping heated platen|
|US6461417||Aug 24, 2000||Oct 8, 2002||Xerox Corporation||Ink compositions|
|US6505927||Dec 15, 1999||Jan 14, 2003||Eastman Kodak Company||Apparatus and method for drying receiver media in an ink jet printer|
|US6509393||Mar 22, 2001||Jan 21, 2003||Xerox Corporation||Phase change inks|
|US6516142||Feb 12, 2001||Feb 4, 2003||Watlow Polymer Technologies||Internal heating element for pipes and tubes|
|US6519835||Aug 18, 2000||Feb 18, 2003||Watlow Polymer Technologies||Method of formable thermoplastic laminate heated element assembly|
|US6539171||Jan 8, 2001||Mar 25, 2003||Watlow Polymer Technologies||Flexible spirally shaped heating element|
|US6541744||Feb 12, 2001||Apr 1, 2003||Watlow Polymer Technologies||Packaging having self-contained heater|
|US6554514||Nov 16, 2001||Apr 29, 2003||Hewlett-Packard Development Co., L.P.||Conductive heating of print media|
|US6679640||Jan 28, 2002||Jan 20, 2004||Vutek, Incorporated||Printing system web guide coupling assembly|
|US6744978||Jul 19, 2001||Jun 1, 2004||Watlow Polymer Technologies||Small diameter low watt density immersion heating element|
|US6748646||Feb 21, 2002||Jun 15, 2004||Watlow Polymer Technologies||Method of manufacturing a molded heating element assembly|
|US6857803 *||Jan 28, 2002||Feb 22, 2005||Vutek, Inc.||Printing system web guide with a removable platen|
|US7134750 *||Apr 22, 2004||Nov 14, 2006||Konica Minolta Business Technologies, Inc.||Ink jet printer|
|US7237872||May 2, 1995||Jul 3, 2007||Fujifilm Dimatrix, Inc.||High resolution multicolor ink jet printer|
|US7410251 *||Nov 17, 2004||Aug 12, 2008||Samsung Electronics Co., Ltd.||Apparatus for forming a thin film using an inkjet printing method|
|US7690779||Jun 20, 2007||Apr 6, 2010||Fujifilm Dimatix, Inc.||High resolution multicolor ink jet printer|
|US7703911 *||Jul 21, 2008||Apr 27, 2010||Samsung Electronics Co., Ltd.||Apparatus for forming a thin film using an inkjet printing method|
|US8197024 *||Oct 29, 2009||Jun 12, 2012||Xerox Corporation||Cooler for a printer|
|US8506063||Feb 7, 2011||Aug 13, 2013||Palo Alto Research Center Incorporated||Coordination of pressure and temperature during ink phase change|
|US8545004 *||Jan 18, 2012||Oct 1, 2013||Palo Alto Research Center Incorporated||Contactless ink leveling method and appartus|
|US8556372||Feb 7, 2011||Oct 15, 2013||Palo Alto Research Center Incorporated||Cooling rate and thermal gradient control to reduce bubbles and voids in phase change ink|
|US8562117||Feb 7, 2011||Oct 22, 2013||Palo Alto Research Center Incorporated||Pressure pulses to reduce bubbles and voids in phase change ink|
|US8721057||Oct 11, 2012||May 13, 2014||Xerox Corporation||System for transporting phase change ink using a thermoelectric device|
|US8882259 *||Aug 8, 2012||Nov 11, 2014||Seiko Epson Corporation||Recording apparatus|
|US8974045||Apr 13, 2011||Mar 10, 2015||Fujifilm Dimatix, Inc.||Phase-change ink jetting|
|US8991997||Sep 19, 2013||Mar 31, 2015||Palo Alto Research Center Incorporated||Device for leveling ink under a thermal gradient|
|US20040191425 *||Nov 9, 2001||Sep 30, 2004||Norbert Peytour||Method of applying a relief inscription to a substrate made of plastic, and a device for implementing the method|
|US20050041053 *||Apr 22, 2004||Feb 24, 2005||Konica Minolta Business Technologies, Inc.||Ink jet printer|
|US20050104945 *||Nov 17, 2004||May 19, 2005||Samsung Electronics Co., Ltd.||Apparatus for forming a thin film using an inkjet printing method|
|US20060035013 *||Aug 18, 2005||Feb 16, 2006||Gilles Leroux S.A.||Method for applying a relief inscription to a substrate made of plastic, and device for implementing the method|
|US20070068404 *||Sep 29, 2005||Mar 29, 2007||Edwin Hirahara||Systems and methods for additive deposition of materials onto a substrate|
|US20080018682 *||Jun 20, 2007||Jan 24, 2008||Fujifilm Dimatix, Inc.||High Resolution Multicolor Ink Jet Printer|
|US20080024557 *||Jul 26, 2006||Jan 31, 2008||Moynihan Edward R||Printing on a heated substrate|
|US20080158327 *||Jan 3, 2007||Jul 3, 2008||Robert P. Siegel||Portable system for large area printing|
|US20080221543 *||Apr 30, 2007||Sep 11, 2008||Todd Wilkes||Disposable absorbent product having a graphic indicator|
|US20080273072 *||Jul 21, 2008||Nov 6, 2008||Jin-Koo Chung||Apparatus for forming a thin film using an inkjet printing method|
|US20090185004 *||Jul 23, 2009||Seiko Epson Corporation||Droplet discharge head and pattern forming device|
|US20100156986 *||Dec 15, 2009||Jun 24, 2010||Canon Kabushiki Kaisha||Ink jet printing apparatus|
|US20100188469 *||Jan 19, 2010||Jul 29, 2010||Seiko Epson Corporation||Recording apparatus|
|US20110102491 *||Oct 29, 2009||May 5, 2011||Xerox Corporation||Cooler For A Printer|
|US20120120169 *||Jan 18, 2012||May 17, 2012||Palo Alto Research Center Incorporated||Contactless ink leveling method and appartus|
|US20120200630 *||Feb 7, 2011||Aug 9, 2012||Palo Alto Research Center Incorporated||Reduction of bubbles and voids in phase change ink|
|US20130050370 *||Aug 8, 2012||Feb 28, 2013||Seiko Epson Corporation||Recording apparatus|
|CN102282021B||Jan 28, 2010||Jun 25, 2014||株式会社御牧工程||Inkjet printer|
|WO1989012215A1 *||May 18, 1989||Dec 14, 1989||Spectra Inc||Controlled ink drop spreading in hot melt ink jet printing|
|WO1990005893A1 *||Oct 20, 1989||May 31, 1990||Spectra Inc||Hot melt ink printing|
|WO1991004799A1 *||Sep 4, 1990||Apr 18, 1991||Spectra Inc||Treatment of hot melt ink images|
|WO1992002782A1 *||Jun 12, 1991||Feb 20, 1992||Spectra Inc||Subttractive color hot melt ink reflection images on opaque substrates|
|WO1999039910A1||Oct 19, 1998||Aug 12, 1999||Spectra Inc||Bar code printing on cartons with hot melt ink|
|U.S. Classification||347/18, 347/102, 250/316.1, 250/319, 346/104, 346/25, 346/99|
|International Classification||B41J2/195, G03G15/16, B41J2/01, G01D15/16, G01D9/00, B41J2/175|
|Cooperative Classification||B41J11/02, B41J2/17593, B41J11/0085|
|European Classification||B41J11/02, B41J11/00S, B41J2/175M|
|Sep 9, 1987||AS||Assignment|
Owner name: SPECTRA, INC.,NEW HAMPSHIRE
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:SPEHRLEY, CHARLES W. JR.;CREAGH, LINDA T.;SCHAFFER, ROBERT R.;REEL/FRAME:004770/0547
Effective date: 19870908
|Sep 4, 1990||RR||Request for reexamination filed|
Effective date: 19900713
|Oct 25, 1991||FPAY||Fee payment|
Year of fee payment: 4
|Oct 29, 1991||B1||Reexamination certificate first reexamination|
|Dec 13, 1995||FPAY||Fee payment|
Year of fee payment: 8
|Dec 13, 1999||FPAY||Fee payment|
Year of fee payment: 12
|Dec 19, 2003||AS||Assignment|